Mouse cursor freezing and locking up PC on XP

I have a problem on windows XP where the mouse freezes once I log out of AOL 9.0. Sometimes just in general I leave the PC on and come back and the mouse is frozen. I have a wireless logitech mouse, I updated all its most recent drivers and still I have problems.

When you try to move the mouse again, does the red light come on, or does nothing happen? If the light comes on then the computer froze or batteries are dieing, if the light comes on, then you might not be getting a good signal. Check both of these situations and post back.

I have also a wireless Logitech mouse (MX700) which shows the same problems, mouse freezing up out of the blue, taking the keyboard with it. Only a reset will bring my PC back to life.
I have no modem installed (broadband: NIC-->router-->power over ethernet-->antenna on the roof-->wireless connection to provider).
I tried with all Logitech driver versions, the standard Win2000 driver, MS-Intellisoft 4.1 driver, all to no avail.
In the end I had to go back to my good old trusted cabled Logitech Mouseman+.